Here is a stock ROM, MTK Backup for Tecno S9s which is also known as Tecno S9-s.
With this Tecno S9s flash file, you can flash stock ROM back to your Tecno S9s using SP Flash Tool. This is mostly required when you have software issues with your Tecno android devices, and in most cases, flashing stock ROM on Tecno android devices corrects all software errors if you know how to do it.
Below here is the download link for the stock ROM. You may also see the tutorial page on how to flash stock ROM on Tecno and other MTK android devices below.
Tecno S9s, S9s Stock ROM Download Details:
ROM Size: -
S9s Stock ROM Download Link: Download Tecno S9s ROM Here
Tutorials for Flashing Stock ROM On Tecno S9s
How to Flash Stock ROM on Tecno and other MTK Android Devices Here
Video Tutorial On How to Flash MTK Android
Source: List of All Tecno Android Device Stock ROM and Flash Files